The Spanish turbot aquaculture sector holds a top position in the international market. Thisactivity is mainly developed along the Galician coast (NW Spain). This article evaluates the environmentalperformance of Galician turbot aquaculture according to the Life Cycle Assessment (LCA) methodology.Previously, on account of the expected relevance of feed for aquaculture, marine aquafeed production wasassessed from an LCA perspective. Environmental characterization results for marine feed production led toidentify aquafeed formulation as the focus for improvement actions. Furthermore, the environmental profile of feed for continental aquaculture was estimated and compared to that of marine aquafeed. The LCA of marine aquafeed was then implemented into the case study of Galician turbot aquaculture. Electricity use in hatching facilities arose as the main hot spot, ahead of aquafeed and diesel use in ongrowing plants.LCA proved to be a useful tool to provide chain transparency and accountability throughout these case studies.